&nbsp Our Valuable Native Grasslands, Better Pastures Naturally&nbsp Proceedings of the Second National Conference of the Native Grasses Association

Effective Pasture Cropping

Colin Seis

"Winona" Gulgong NSW 2850

Abstract

For the past 100 years Australian agriculture has been declining financially and environmentally. Much criticism has been levelled at farm managers and landholders for contributing to the destruction of soils, water and grasslands. Often this criticism is from people with little or no understanding of what was actually happening for those on the land. The landowners were only working with the knowledge that they had at the time, and like today, they had to keep the bank manager from the door.

Landholders in general, from the 1940s onwards, found themselves reliant on "improved pastures" utilising introduced grass species and fertilisers to replace native pastures that were lost by a variety of means. A similar situation still exists today. Land degradation in the form of increasing soil acidity, weed invasion and a rising saline water table began to appear on "Winona" during the 1970s.

The current land management system on "Winona" has turned things around and the natural resource base is improving. High density short duration grazing (pulsed grazing) is combined with cereal crops direct drilled into standing native perennial pasture (pasture cropping) on the same land in the same year. As a result, the density and diversity of native grasses are rapidly increasing, as are profit margins.

Introduction

For the last 100 years Australian agriculture has been declining financially and environmentally. There has been much criticism of how farm managers and landholders have destroyed our soils, water and grasslands. This is often from people who have no understanding of what was really happening to those on the land. The landowners were only working with the knowledge that they had at the time, and like today, had to keep the bank manager from the door. People that are critical of past and present farming methods should provide alternatives. They rarely do.

Background

Native grasslands and grassy woodlands were a feature of the Australian landscape prior to European settlement. The early settlers were presented with a rich but fragile and complex ecosystem. They approached farming with methods that were entirely unsuitable and the result was the rapid decline of the quality of the vegetation and soils. This was caused by overstocking, inappropriate cropping methods, the decimation of much of the native fauna and by the introduction of exotic animals such as the fox and the rabbit.

Very quickly, the variety of native grasses diminished, woody regrowth began appearing, and landholders had no choice but to seek improvements that would sustain their survival "on the land". Settlers who took up landholdings in the early to mid 1800s had problems finding enough timber for buildings and fences. By comparison, settlers who took up landholdings after the early 1900s spent much of their time clearing re-growth timber to establish pastures. By then many of the valuable native species had been lost from grassy ecosystems.

Pasture improvement with sub-clover and superphosphate was one of the early methods of combating the problems of declining pastures and although trial work was done in the 1920s graziers didn't implement it until the 1940s.

Land management on "Winona"

The Seis family settled in the Gulgong district in 1868 and were instrumental, along with millions of rabbits and European based agricultural methods, in causing the damage to our soils, water and grasslands. In 1947, my father, Harry Seis set about restoring the family property "Winona" by fixing the erosion problems and introducing a pasture improvement program of subclover, ryegrass and tons of very cheaply priced, subsidised superphosphate.

This system worked very well for 30 years being very productive and doubling the carrying capacity, but problems were apparent by the 1970s in the form of increasing soil acidity, weed invasion and a rising saline water table. These problems had various causes but primarily sub clover, which had created an annual summer drought syndrome by out-competing most of the summer growing native grasses when they commenced their growth period in spring.

By the 1970s the increase in the price of superphosphate was starting to make it uneconomical to use. With all the problems that were associated with this so-called "improved pasture system" another way had to be found to run "Winona" that would be both financially and environmentally sound. After years of soul-searching and beer drinking, barnstorming and think tanks, Colin Seis, Darryl Cluff and the non-drinking member of the trio, Christine Jones, developed a technique that would combine grazing and cropping into a single land management system.

The current land management system on "Winona" is a combination of high density short duration grazing (pulsed grazing) with pasture cropping, that is, the direct drilling of a cereal crop into an existing native perennial pasture.

Pulsed grazing is based on the cell grazing principle of large mobs of sheep, in this case, 2000 per mob, that rotate around a number of smaller sized paddocks [average 20 ha]. The sheep are moved every 4-6 days and this creates a rest period of 70-90 days before each paddock is re-grazed. This grazing method has significantly increased the number and density of native perennial grass species in less than two years.

By using large numbers of sheep as weed controllers prior to the direct drilling of the crop, chemical use has been reduced. As the groundcover of native grass increases chemical use can probably be eliminated. The pasture cropping technique improves the diversity of native pastures. We do not, as yet, fully understand the reason for this.

Pastures continue to improve every year. The first grasses to appear were grazing tolerant species such as Bothriochloa (redgrass) and Austrostipa (speargrasses), but more productive species such as Paspalidium, Austrodanthonia, Microlaena and Elymus are quickly returning. Superphosphate has not been used on any of the pastures for 23 years. The carrying capacity of "Winona" is now 3 dse/acre [7.5 sheep/ha]. This is around the same number of sheep /ha as the old system but without the expensive inputs.

"Winona" now produces approximately 30kg of 19-micron wool per hectare and the average cost is $2.05/kg. The fertiliser costs of the old system would be around $22,000 a year at today's prices, which would increase costs to over $3/kg with no gain in wool production.

The paddocks that are used for pasture cropping are grazed about every four weeks during the summer and autumn months at about 100 sheep/ha for four days at a time to control weeds and reduce the dry matter bulk. Glyphosate or Sprayseed is applied at about 1L/ha in late April-May before sowing the crop - when the summer growing native grasses are becoming winter dormant. Therefore, only the annual weeds such as saffron thistle, Vulpia and Paterson's curse are killed. The harvest results have been excellent with wheat yields up to 3.9 t/ha with total costs as low as $65/ha. A bonus is the extra grazing up to the point of sowing and then the excellent grazing after the crop is harvested.

There is an increase in grazing of up to 6 months compared to traditional cropping methods where ground preparation starts 6 months prior to the crop being sown. Usually this leaves bare paddocks with no stock feed, and contributes to erosion, poor water use and rising water tables. This 6 months extra grazing is worth $70-$80/ha in wool production. With traditional cropping practices, this is a production loss that is rarely accounted for in cropping budgets. In reality 20%- 25% of a property can be cropped without any reduction in stock numbers.

Oats can also be direct sown into native grasses using the pasture cropping method, and used to fill the winter feed gap in a grazing enterprise. The cost of this technique is even lower than for pasture crop grain production, due to lower requirements for herbicide and fertiliser.

Conclusion

Australian agriculture can no longer afford the "pasture improvement" system that has been in place for the last 50 years. It filled a very important production niche for many years but the cost of propping up a system with fertilisers can no longer be afforded financially or environmentally. There are other options such as the low input system described, which has had a profound impact on both the financial and environmental structure on "Winona".

Acknowledgments

I wish to thank Darryl Cluff and Christine Jones for contributing to the development of the ideas presented in this paper. Sincere thanks also to Mike Byron for valuable editorial assistance.